In shops: Cold hard cash or Pre-Payed Credit Card (unless facility doesn't have an online checking system like a petrol station, also saves them from asking me the stupid question "any proof of ID?" when buying 18 rated Games, Movies, Anime and so on.)

Online: Pre-Pay Credit Card (no fees when buying stuff from Japan or US with mines.)

Subscription based like Satellite TV and broadband: Direct Debit via bank card, since it has safeguards in place.